The present invention relates to optical fiber distribution frames. More particularly, the present invention relates to an improved optical fiber cable distribution shelf for mounting in a conventional optical fiber distribution frame. The frame normally includes a plurality of cable distribution shelves mounted therein and wherein each cable distribution shelf includes a plurality of optical connectors for connecting external fiber optic cable with selected optical fibers leading to individual telephone, computer systems or the like.
Optical fiber distribution frames are routinely used in telecommunications as an interface between optical fiber feeder and optical fiber distribution cables. The frames usually include a plurality of drawers or shelves which each include a panel within which is mounted an array of optical fiber connectors. It is preferable for distribution frame customers to have quick and easy access to the optical fibers and the drawers or shelves from the front of the distribution frame. A typical approach to providing this feature is to have the connector panel rotatably mounted on a vertical hinge as described in U.S. Pat. No. 4,708,430 to Donaldson et al. The patent discloses a cabinet with a removable front cover and a stack of splice trays positioned therein and an array of optical connectors mounted on a front panel. In order to gain access to the inside of the cabinet the front panel is hinged to the cabinet at one side so as to pivot open to expose the interior of the cabinet. A major shortcoming of the distribution cabinet is that it is necessary to detach the stack of splice trays and move the stack of splice trays forwardly in order for the trays to be readily accessible for repair or testing.
An alternative distribution frame is disclosed in Cooper U.S. Pat. No. 4,898,448 wherein a fiber distribution panel is disclosed that provides a slidable drawer that includes a slidably moveable integrated connector panel, splice shelf and cable storage unit. It has also been suggested that each tray including the panel containing the array of optical fiber connectors be pivotally mounted to a cabinet such as seen in Gotto et al. U.S. Pat. No. 4,832,436.
U.S. Pat. No. 5,129,030 to Petrunia discloses an optical fiber distribution frame including a plurality of shelves wherein each shelf has a tray positioned therein that includes an array of optical fiber connectors, and wherein each tray is slidably mounted within its corresponding shelf so that the tray can be pulled out horizontally from the shelf. Further, each slidable tray can be pivoted downward to provide front access to the optical fibers and optical fiber connectors in the distribution frame in which the plurality of tray containing shelves are mounted.
The present invention overcomes the prior art shortcomings by providing a cable distribution shelf for connecting incoming optical fiber cables with fiber optic patch cords or similar fiber optic cables. The shelf includes a housing comprising a middle plate extending transversely therethrough so as to define a front bay and a rear bay within the housing. The middle plate defines two or more laterally spaced-apart apertures therein. A first vertically-spaced stack of trays is pivotably mounted to the middle plate so that each tray is moveable from (1) an operative position with the front thereof positioned in a first middle plate aperture and substantially flush with the middle plate into (2) an extended forwardly pivoted position with the front of the tray facing inwardly within the housing. A second vertically-spaced stack of trays is provided and pivotably mounted to the middle plate so that each tray is moveable from (1) an installed position with the front thereof positioned in a second middle plate aperture and substantially flush with the middle plate into (2) an extended forwarded pivoted position with the front of the tray facing inwardly within the housing. A plurality of adapters are mounted to the front of each tray of the first and second vertically-spaced stacks of trays such that the adapters serve to connect incoming fiber optical connectors to outgoing fiber optical connectors.
Alternatively, other embodiments of the cable distribution shelf of the present invention contemplate that a vertical stack of one or more trays can be mounted to the middle plate so as to be positioned in either the first middle plate aperture or the second middle plate aperture and that no additional tray stack be mounted to the middle plate and positioned in the remaining middle plate aperture. Further, applicants contemplate that regardless of whether the cable distribution shelf of the present invention utilizes a singular stack of trays or two stacks of trays, the singular or dual stacks can each include between one and six trays and that each tray can include up to twelve or twenty-four adapters for connecting incoming optical fiber connectors (single or multiple) to outgoing optical fiber connectors. In this fashion, the cable distribution shelf of the present invention can accommodate up to twelve trays in the rear bay thereof that serve to connect up to a total of 144 optical fibers (using single fiber connectors) carried by the incoming optical fiber cables and selectively connected to the same compliment of 144 optical fibers of outgoing fiber optic patch cords or similar fiber optic cables.
It is therefore an object of the present invention to provide an improved optical fiber cable distribution shelf for use with an optical fiber distribution frame.
It is another object of the present invention to provide an improved optical fiber cable distribution shelf for use with an optical fiber distribution frame that provides for enhanced cable management in the front and rear of the shelf so as to render the shelf easier to install and simpler to integrate.
It is another object of the present invention to provide an improved optical fiber cable distribution shelf for use with a cable distribution frame wherein both the front and rear of the shelf are easily accessible.
It is another object of the present invention to provide an improved optical fiber cable distribution shelf for use with a cable distribution frame wherein if only front access is possible to the shelf, the rear side of the optical fiber adapters mounted to the shelf will still be accessible.
Some of the objects of the invention having been stated, other objects will become evident as the description proceeds when taken in connection with the accompanying drawings described herein below.